We also have that nude beach to open, yeah.Maybe even Harriet's too with the check ups during the weekly board meeting. I suppose it's even possible that it occurs gradually with a scene here and a scene there in intervening updates as the students become more and more exposed and less inhibited over time. Especially with the likes of Liz and the accidental nudist (Emily I think. Certainty escapes me for the moment). It could cause her to struggle more with her repressed desires to the point she either lets go or the HM has to intervene in order to 'maintain the good order and smooth running of the school'.
You know it's bad when the HM has fewer sexual thoughts when going into the girls' locker room, than Ruth. XD